Flow conditions, photochemical reaction under

The same flow-type photochemical reactor as shown in Fig. 8.4 was used here, although the reaction time was lunger and the reaction temperature was from 298-353 K. As shown in Fig. 8.17, MC was transformed to dichloroethene (CH2CC12) on Ti02 in the dark and under dry conditions. The MC consumption increased with the reaction temperature. The ratio of MC consumed to CH2CC12 produced was close to unity, indicating that the elimination of HC1 from MC predominantly occurred in this temperature range. 

PETP destruction under atmospheric conditions, as a result of photochemical reaction, flows mainly under the action of ultra-violet rays with 1=300-330 nm [220]. Energy of these waves is about 1% of the total energy of the sunlight. Authors connect this fact with the presence of absorption maximum of PETP itself in this region of the spectrum. 

Photochemistry can potentially provide an environmental-friendly and green approach to chemical synthesis however, the ability to scale-up such photochemical processes is marred with problems, which are mainly associated with the power of light sources. The fact that a large number of microreactors are manufactured in glass, quartz, or transparent polymers is ideal for conducting photochemical processes, as the path length of such reactors is small meaning that it is very easy to irradiate the reaction mixture within the channel. Compared to other examples of chemical synthesis in flow reactors, the number of photochemical transformations performed under flow conditions has until recently been very limited. Early examples included benzopinacol formation [1], synthesis of cycloaddition products [2], and photosensitized diastereodifferentiation [3]. 

In this chapter we report and analyze examples of asymmetric organocatalytic reactions under non-classical conditions high pressure, microwave heating, ultrasound irradiation, and ball milling. Organocatalytic processes based on photochemical or electrochemical activation as well as applying continuous-flow reactors are not included. 

Mechanisms of aliphatic PA photooxidation under light action in the conditions of amide group absorption [4] where studied. These reactions way flow under the action of short-wave light which boundary at the Earth s surface is 290 nm. The main result of investigations was discovery of the role of radical - CONHCHCH - (Ri ), being the precursor of all basic products of alkylamide oxidation, for example, RC O and Pi, formed at primary photochemical process of photodissociation of amide bond according to the reaction ... 

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